Overexpression of B7H5/CD28H is associated with worse survival in human gastric cancer

VISTA: A Novel Checkpoint for Cancer Immunotherapy

V-domain Ig suppressor of T cell activation (VISTA) is a recently identified member of the B7 family of immunoregulatory proteins. It is pivotal for maintaining T cell quiescence and exerts a significant regulatory influence on the immune response to tumors. Accumulating clinical evidence suggests that the influence of VISTA on tumor immunity is more nuanced than initially postulated. Although these revelations add layers of complexity to our understanding of the function of VISTA, they also offer novel avenues for scientific inquiry and potential therapeutic targets. In this review, we scrutinize the current literature pertaining to the expression of VISTA in various of malignancies, aiming to elucidate its intricate roles within the tumor microenvironment and in cancer immunotherapy.

Immune checkpoints signature-based risk stratification for prognosis of patients with gastric cancer

Until now, few researches have comprehensive explored the role of immune checkpoints (ICIs) and tumor microenvironment (TME) in gastric cancer (GC) patients based on the genomic data. RNA-sequence data and clinical information were obtained from The Cancer Genome Atlas Stomach Adenocarcinoma (TCGA-STAD) database, GSE84437 and GSE84433. Univariate Cox analysis identified 60 ICIs with prognostic values, and these genes were then subjected to NMF cluster analysis and the GC samples (n = 804) were classified into two distinct subtypes (Cluster 1: n = 583; Cluster 2: n = 221). The Kaplan-Meier curves for OS analysis indicated that C1 predicted a poorer prognosis. The C2 subtype illustrated a relatively better prognosis and characteristics of "hot tumors," including high immune score, overexpression of immune checkpoint molecules, and enriched tumor-infiltrated immune cells, indicating that the NMF clustering in GC was robust and stable. Regarding the patient's heterogeneity, an ICI-score was constructed to quantify the ICI patterns in individual patients. Moreover, the study found that the low ICI-score group contained mostly MSI-low events, and the high ICI-score group contained predominantly MSI-high events. In addition, the ICI-score groups had good responsiveness to CTLA4 and PD-1 based on The Cancer Immunome Atlas (TCIA) database. Our research firstly constructed ICIs signature, as well as identified some hub genes in GC patients.

TMIGD2 as a potential therapeutic target in glioma patients

Introduction

Among all types of central nervous system cancers, glioma remains the most frequent primary brain tumor in adults. Despite significant advances in immunomodulatory therapies, notably immune checkpoint inhibitors, their effectiveness remains constrained due to glioma resistance. The discovery of TMIGD2 (Transmembrane and Immunoglobulin Domain Containing 2) as an immuno-stimulatory receptor, constitutively expressed on naive T cells and most natural killer (NK) cells, has emerged as an attractive immunotherapy target in a variety of cancers. The expression profile of TMIGD2 and its significance in the overall survival of glioma patients remains unknown.

Methods

In the present study, we first assessed TMIGD2 mRNA expression using the Cancer Genome Atlas (TCGA) glioma transcriptome dataset (667 patients), followed by validation with the Chinese Glioma Genome Atlas (CGGA) cohort (693 patients). Secondly, we examined TMIGD2 protein staining in a series of 25 paraffin-embedded blocks from Moroccan glioma patients. The statistical analysis was performed using GraphPad Prism 8 software.

Results

TMIGD2 expression was found to be significantly higher in astrocytoma, IDH-1 mutations, low-grade, and young glioma patients. TMIGD2 was expressed on immune cells and, surprisingly, on tumor cells of glioma patients. Interestingly, our study demonstrated that TMIGD2 expression was negatively correlated with angiogenesis, hypoxia, G2/M checkpoint, and epithelial to mesenchymal transition signaling pathways. We also demonstrated that dendritic cells, monocytes, NK cells, gd T cells, and naive CD8 T cell infiltration correlates positively with TMIGD2 expression. On the other hand, Mantel-Cox analysis demonstrated that increased expression of TMIGD2 in human gliomas is associated with good overall survival. Cox multivariable analysis revealed that TMIGD2 is an independent predictor of a good prognosis in glioma patients.

Discussion

Taken together, our results highlight the tight implication of TMIGD2 in glioma progression and show its promising therapeutic potential as a stimulatory target for immunotherapy.

KIR3DL3-HHLA2 and TMIGD2-HHLA2 pathways: The dual role of HHLA2 in immune responses and its potential therapeutic approach for cancer immunotherapy

BACKGROUND

T cells and natural killer (NK) cells are essential components of the immune system and are regulated by coinhibitory and costimulatory molecules in which the B7 family and CD28 family play significant roles. Previous immune checkpoint studies on B7/CD28 family members, such as PD-1, have led to remarkable success in cancer immunotherapy. However, there is still a need to find new immune checkpoint molecules. Recent studies have demonstrated that HHLA2 exerts inhibitory and stimulatory functions on the immune system by binding to different receptors on different sites. However, the pathways between HHLA2 and its two receptors on T cells and NK cells remain controversial.

AIM OF REVIEW

Here, we reviewed recent studies about HHLA2 ligand interactions with KIR3DL3 and TMIGD2. We focused on elucidating the pathways between KIR3DL3/TMIGD2 and HHLA2 as well as their function in tumour progression. We also addressed the relationship between HHLA2 expression and the clinical prognosis of cancer patients.

KEY SCIENTIFIC CONCEPTS OF REVIEW

KIR3DL3/TMIGD2-HHLA2 may represent novel pathways within the tumour microenvironment and serve as crucial immune checkpoints for developing novel therapeutic drugs against human cancer.

GPR30 Activation Promotes the Progression of Gastric Cancer and Plays a Significant Role in the Anti-GC Effect of Huaier

Gastric cancer (GC) is one of the most common types of cancer. The n-butanol extract of Huaier (NEH) is the alcohol-soluble part extracted by the systematic solvent method, which is effective against gastric cancer (GC). However, the mechanism of action of NEH remains unclear. In this study, we aim to evaluate the clinical relevance of GPR30 expression in GC patients and the role of the GPR30/PI3K/AKT signalling pathway in the anti-GC effect of NEH. The expression of GPR30 was examined using immunohistochemistry. Cell counting kit 8 (CCK-8) assay, wound healing, and transwell experiments were used to investigate the viability, migration, and invasion of gastric cancer cells. Western blotting was used to detect the expression of GPR30 and its downstream signalling molecules of the PI3K/AKT signalling pathway. Gastric cancer patient-derived xenografts (PDX) mouse model was used to evaluate the antitumor effect of NEH in vivo. In addition, the graded doses and the maximum tolerated dose of NEH were administered intraperitoneally into the mice for acute toxicity test. We demonstrate that GPR30 expression in GC tissues was significantly higher than that in corresponding adjacent noncancerous tissues and the expression of GPR30 was correlated with a poor prognosis in GC patients. Moreover, GPR30 expression was involved in the migration and invasion of GC cells in vitro. Additionally, we found that NEH can suppress the growth of GC in patient-derived xenograft tumors in vivo. Furthermore, NEH inhibited the proliferation, migration, and invasion in GC cells in a concentration-dependent manner through inhibiting the GPR30-mediated PI3K/AKT signalling pathway in vitro. Acute toxicity test showed that NEH caused no toxic reaction or death and the maximum tolerated dose of NEH in mice was greater than 1600 mg/kg. Our results demonstrate that the high expression of GPR30 is an independent factor of poor prognosis in patients with GC and NEH could be a new agent for the treatment of gastric cancer.

Alleviating Oxidative Damage-Induced Telomere Attrition: a Potential Mechanism for Inhibition by Folic Acid of Apoptosis in Neural Stem Cells

DNA oxidative damage can cause telomere attrition or dysfunction that triggers cell senescence and apoptosis. The hypothesis of this study is that folic acid decreases apoptosis in neural stem cells (NSCs) by preventing oxidative stress-induced telomere attrition. Primary cultures of NSCs were incubated for 9 days with various concentrations of folic acid (0-40 µM) and then incubated for 24 h with a combination of folic acid and an oxidant (100-µM hydrogen peroxide, H₂O₂), antioxidant (10-mM N-acetyl-L-cysteine, NAC), or vehicle. Intracellular folate concentration, apoptosis rate, cell proliferative capacity, telomere length, telomeric DNA oxidative damage, telomerase activity, intracellular reactive oxygen species (ROS) levels, cellular oxidative damage, and intracellular antioxidant enzyme activities were determined. The results showed that folic acid deficiency in NSCs decreased intracellular folate concentration, cell proliferation, telomere length, and telomerase activity but increased apoptosis, telomeric DNA oxidative damage, and intracellular ROS levels. In contrast, folic acid supplementation dose-dependently increased intracellular folate concentration, cell proliferative capacity, telomere length, and telomerase activity but decreased apoptosis, telomeric DNA oxidative damage, and intracellular ROS levels. Exposure to H₂O₂ aggravated telomere attrition and oxidative damage, whereas NAC alleviated the latter. High doses of folic acid prevented telomere attrition and telomeric DNA oxidative damage by H₂O₂. In conclusion, inhibition of telomeric DNA oxidative damage and telomere attrition in NSCs may be potential mechanisms of inhibiting NSC apoptosis by folic acid.

The Positive and Negative Immunoregulatory Role of B7 Family: Promising Novel Targets in Gastric Cancer Treatment

Gastric cancer (GC), with a heterogeneous nature, is the third leading cause of death worldwide. Over the past few decades, stable reductions in the incidence of GC have been observed. However, due to the poor response to common treatments and late diagnosis, this cancer is still considered one of the lethal cancers. Emerging methods such as immunotherapy with immune checkpoint inhibitors (ICIs) have transformed the landscape of treatment for GC patients. There are presently eleven known members of the B7 family as immune checkpoint molecules: B7-1 (CD80), B7-2 (CD86), B7-H1 (PD-L1, CD274), B7-DC (PDCD1LG2, PD-L2, CD273), B7-H2 (B7RP1, ICOS-L, CD275), B7-H3 (CD276), B7-H4 (B7x, B7S1, Vtcn1), B7-H5 (VISTA, Gi24, DD1α, Dies1 SISP1), B7-H6 (NCR3LG1), B7-H7 (HHLA2), and Ig-like domain-containing receptor 2 (ILDR2). Interaction of the B7 family of immune-regulatory ligands with the corresponding receptors resulted in the induction and inhibition of T cell responses by sending co-stimulatory and co-inhibitory signals, respectively. Manipulation of the signals provided by the B7 family has significant potential in the management of GC.

Prognostic value of HHLA2 expression in solid tumors: A meta-analysis based on the Chinese population

BACKGROUND

Human endogenous retrovirus-H long terminal repeat-associating protein 2 (HHLA2), a newly discovered member of the B7 family, is overexpressed in numerous tumors. However, the prognostic impact of HHLA2 in human cancers remains controversial. Thus, we performed this meta-analysis to explore the prognostic value of HHLA2 in Chinese patients with solid tumors.

METHODS

PubMed, Embase, Web of Science, Chinese National Knowledge Infrastructure, and WanFang databases were systematically searched for eligible studies that evaluated the impact of HHLA2 on overall survival (OS) in patients with cancer. Hazard ratios (HRs) and 95% confidence intervals (CIs) were combined to evaluate the association between HHLA2 expression and OS in solid tumors. Odds ratios (ORs) and 95% CIs were pooled to assess the correlation between HHLA2 expression and clinicopathological characteristics in solid tumors.

RESULTS

A total of 12 studies, including 15 cohorts and 1747 patients, were included in this meta-analysis. We found that high HHLA2 expression was significantly associated with shorter OS (HR = 1.65, 95% CI: 1.12-2.43). Subgroup analysis by cancer type demonstrated that high HHLA2 expression was associated with poor OS in patients with clear cell renal cell carcinoma (HR = 3.42, 95% CI: 2.39-4.91), gastric cancer (HR = 2.03, 95% CI: 1.31-3.16), intrahepatic cholangiocarcinoma (HR = 1.77, 95% CI: 1.24-2.53), lung cancer (HR = 2.14, 95% CI: 1.33-3.44) and other cancer types (HR = 2.08, 95% CI: 1.34-3.24), but not in patients with epithelial ovarian cancer (HR = 0.52, 95% CI: 0.08-3.56). Nevertheless, high HHLA2 expression was associated with better OS in patients with pancreatic ductal adenocarcinoma (HR = 0.45, 95% CI: 0.32-0.64). Furthermore, high HHLA2 expression was associated with old age (OR = 1.30, 95% CI: 1.03-1.63), lymph node metastasis (OR = 1.99, 95% CI: 1.41-2.81), and vascular invasion (OR = 1.69, 95% CI: 1.18-2.42).

CONCLUSIONS

HHLA2 may serve as a potential prognostic biomarker for solid tumors in Chinese population, by predict the prognosis of cancer patients based on their tumor types.

Efficacy of Conversion Surgery Following Apatinib Plus Paclitaxel/S1 for Advanced Gastric Cancer With Unresectable Factors: A Multicenter, Single-Arm, Phase II Trial

Objective: Conversion therapy (surgical resection after chemotherapy) is a promising option for unresectable gastric cancer (GC) patients. Addition of anti-angiogenesis drug improves response to chemotherapy. Hence, this study explored the feasibility and efficacy of preoperative paclitaxel (PTX)/S1 chemotherapy combined with apatinib for unresectable GC. Methods: Thirty-one eligible patients with a single unresectable factor were enrolled in this multi-center, single-arm trial. Apatinib (500 mg qd) was administered continuously, while PTX (130 mg/m²) on day 1 and S1 (80 mg/m²) on day 1-14 were given every 3 weeks. The treatment was given for three cycles preoperatively, but the last cycle did not include apatinib. The primary objective measurements included R0 resection rate, objective response rate (ORR) and morbidity of preoperative treatment. Results: Among the 31 patients, 30 patients were evaluable for tumor response, the ORR to preoperative treatment was 73.3%. Eighteen of 30 patients underwent surgery, and R0 resection was achieved in 17 patients. The patients who underwent the conversion surgery had a superior OS compared with those who did not (3 years OS: 52.9 vs 8.3%, p = 0.001). The surgery was operated after apatinib had stopped for a median duration of 4 weeks. Neither anastomotic leakage nor wound healing complications was observed. No increased bleeding event was observed compared with historical data. During preoperative treatment, grade 3 or 4 toxicities were experienced by 58.1% of the patients. Conclusion: Chemotherapy in combination with apatinib demonstrated higher rates of conversion and R0 resection and a superior survival benefit in initial unresectable GC. It is safe and reasonable to suspend apatinib for 4 weeks before the gastrectomy.

p-MEK expression predicts prognosis of patients with adenocarcinoma of esophagogastric junction (AEG) and plays a role in anti-AEG efficacy of Huaier

The incidence rate of adenocarcinoma of the esophagogastric junction (AEG) is increasing worldwide with poor prognosis and unclear pathogenesis. Trametes robiniophila Murr. (Huaier), a traditional Chinese medicine has been used in the clinical treatment of a variety of solid tumors, including AEG. However, its anticancer components and molecular mechanisms are still unclear. In our previous studies, we have found that Huaier n-butanol extract (HBE) shows the most potent anticancer activity among different extracts. In the present study, we aimed to investigate the clinical relevance of p-MEK expression in AEG patients and the role of the MEK/ERK signaling pathway in the anti-AEG efficacy of HBE in vitro and in vivo. We herein demonstrate that p-MEK expression in AEG tissues was significantly higher than that in paracancerous tissues and correlated with a poor prognosis in AEG patients. We further found that HBE inhibited the colony formation, migration, and invasion in AEG cell lines in a concentration-dependent manner in vitro. HBE also suppressed the growth of AEG xenograft tumors without causing any host toxicity in vivo. Mechanistically, HBE caused the inactivation of the MEK/ERK signaling pathway by dephosphorylating MEK1 at S298, ERK1 at T202, and ERK2 at T185 and modulating the expression of EMT-related proteins. In summary, our results demonstrate that the high expression of p-MEK may be an independent factor of poor prognosis in patients with AEG. The clinically used anticancer drug Huaier may exert its anti-AEG efficacy by inhibiting the MEK/ERK signaling pathway.

P2X7 receptor as an independent prognostic indicator in gastric cancer

Gastric cancer (GC) is one of the foremost causes of cancer-related death around the world. The P2X7 receptor (P2X7R), a member of the P2X7R subfamily of P2 receptors, is a unique molecule that has been shown to affect tumor growth and progression as well as various inflammatory processes, including proliferation of T lymphocytes, release of cytokines, and production of free oxygen radicals. P2X7R has been established as a prognostic parameter in some cancers, and recently, it has been investigated in the development of new targeted therapies. In the present study, we aimed to investigate the prognostic value of P2X7R expression in GC. The expression profile of P2X7R was evaluated immunohistochemically in 156 paraffin-embedded human GC specimens. P2X7R expression was higher in patients with lymph node metastasis than in those without (p < 0.001). P2X7R overexpression was closely related with tumor-infiltrating lymphocytes (TILs) (p = 0.001), vascular invasion (p = 0.006), depth of invasion (p < 0.001), distant metastasis (p < 0.001), and advanced tumor, node, metastasis stage (p < 0.001). Moreover, univariate (hazard ratio [HR] 3.98; 95% confidence interval (CI) 1.89-11.82; p < 0.001) and multivariate (HR 2.24; 95% CI 3.53-12.50; p < 0.001) Cox regression analysis showed that upregulated P2X7R expression clearly correlated with worsened overall survival. In summary, our data revealed that P2X7R may serve as a reliable prognostic parameter and promising therapeutic target for GC.

Overexpression of B7H5/CD28H is associated with worse survival in human gastric cancer

Gastric cancer (GC) is a common malignancy with low 5‐year overall survival (OS). Recently, immune therapy has been used to treat cancer. B7H5 and CD28H are novel immune checkpoint molecules. However, the prognostic value of B7H5/CD28H expression in patients with GC remains unclear. In this study, seventy‐one patients diagnosed with GC were included in this study. Patients' GC tissues and matched adjacent tissue constructed a tissue microarray. The expression levels of B7H5 and CD28H were examined using immunohistochemistry. Correlations between the expression of B7H5 and CD28H and the clinical data were evaluated. We found that the expression of B7H5 and CD28H (both P = .001) were higher in GC tumour tissues than in adjacent noncancerous tissues. B7H5/CD28H expression acted as an independent predictive factor in the OS of patients with GC. High expression of B7H5 and CD28H predicted poor outcome. Patients in the B7H5+CD28H+ group had a lower 5‐year OS compared with patients in the B7H5−CD28− group (4.5% vs 55.6%, P = .001). A significant difference was found in the 5‐year OS between patients in the B7H5+CD28H− and B7H5+CD28H+ groups (33.5% vs 4.5%, P = .006). However, there was no correlation between B7H5 and CD28H expression (P = .844). Therefore, B7H5 and CD28H expression are up‐regulated in GC and are independent prognostic factors for overall survival in patients with GC. Although there was no correlation between B7H5 and CD28H expression, high expression of B7H5 and CD28H predicts poor prognosis, especially when both are highly expressed.